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Occurrence and Integrated Control of Psylla chinensis in Eastern Hebei Province
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作者 Lijuan GAO Longfei LI +2 位作者 Minghui JI Jintao XU Baofeng HAO 《Plant Diseases and Pests》 CAS 2023年第1期14-16,共3页
The paper introduces the damage characteristics and occurrence regularity of Psylla chinensis in pear orchards in eastern Hebei Province,and summarizes the integrated prevention and control techniques of P.chinensis,i... The paper introduces the damage characteristics and occurrence regularity of Psylla chinensis in pear orchards in eastern Hebei Province,and summarizes the integrated prevention and control techniques of P.chinensis,in order to provide a reference for the prevention and control of P.chinensis in eastern Hebei Province. 展开更多
关键词 Eastern hebei Province Psylla chinensis OCCURRENCE CONTROL
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Estimated prevalence and sociodemographic correlates of mental disorders in medical students of Hebei Province,China:A crosssectional study
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作者 Wen-Ting Lu Pei-Hua Hu +22 位作者 Na Li Lan Wang Ran Wang Zeng Wang Mei Song Tian-Yu Zhao Shi-Jie Guo Fan-Fan Huang Bu-Fan Liu Ruo-Jia Ren Li Yang Quan Lin Yue-Hang Xu Na Jin Huan Chen Yuan-Yuan Gao Zhi-Feng Wu Guang-Yu Shi Da-Peng Liu Zhong-Qi Pan Chun-Chao Du Cui-Xia An Xue-Yi Wang 《World Journal of Psychiatry》 SCIE 2023年第5期215-225,共11页
BACKGROUND In China,the identification rate and treatment rate of mental disorders are low,and there are few surveys on the prevalence of mental disorders among college students using diagnostic tools such as Mini-Int... BACKGROUND In China,the identification rate and treatment rate of mental disorders are low,and there are few surveys on the prevalence of mental disorders among college students using diagnostic tools such as Mini-International Neuropsychiatric Interview(MINI),so the prevalence and treatment of mental disorders among college students are unclear.AIM To estimate prevalence of mental disorders among medical students in Hebei Province,and provide guidance for improving their mental health.METHODS This was a cross-sectional study based on an Internet-based survey.Three levels of medical students in Hebei Province were randomly selected(by cluster sampling)for screening.Using the information network assessment system,the subjects scanned the 2D code with their mobile phones,clicked to sign the informed consent,and answered a scale.A self-designed general status questionnaire was used to collect information about age,gender,ethnicity,grade,and origin of students.The MINI 5.0.was used to investigate mental disorders.Data analysis was performed with SPSS software.Statistically significant findings were determined using a two-tailed P value of 0.05.RESULTS A total of 7117 subjects completed the survey between October 11 and November 7,2021.The estimated prevalence of any mental disorders within 12 mo was 7.4%.Mood disorders were the most common category(4.3%),followed by anxiety disorders(3.9%);15.0%had been to psychological counseling,while only 5.7%had been to a psychiatric consultation,and only 10%had received drug therapy in the past 12 mo.CONCLUSION Although the estimated prevalence of mental disorders in medical students is lower than in the general population,the rate of adequate treatment is low.We determined that improving the mental health of medical students is an urgent matter. 展开更多
关键词 hebei sectional COLLEGE
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Development Countermeasures of County-level Edible Fungi Industry in Hebei Province from the Perspective of Rural Revitalization
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作者 Kun TANG Ying WANG +3 位作者 Minhui ZHANG Wenjie CHEN Junhong HU Chunyan XIE 《Asian Agricultural Research》 2023年第11期15-19,23,共6页
In recent years,the edible fungi industry in Hebei Province has developed rapidly,with gradually increased cultivation scale and production output,and has become the pillar industry of the province,playing a certain r... In recent years,the edible fungi industry in Hebei Province has developed rapidly,with gradually increased cultivation scale and production output,and has become the pillar industry of the province,playing a certain role in promoting the development of rural economy and rural revitalization.Based on the in-depth analysis of the development status,future development direction and current constraints of the edible fungi industry in each typical county of Hebei Province in recent years,the paper puts forward corresponding development countermeasures,which has certain reference value for the county-level edible fungi industry of Hebei Province to promote rural revitalization. 展开更多
关键词 hebei Edible fungi industry Rural revitalization Current status analysis
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Magmatic Event at the End of the Archean in Eastern Hebei Province and Its Geological Implication 被引量:87
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作者 GENG Yuansheng LIU Fulai YANG Chonghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期819-833,共15页
By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ... By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ago, the Qingyangshu gabbroic gneiss 2536 Ma, the Yinmahe granodioritic gneiss near Lücao, Lulong County, 2533 Ma, the gabbro-dioritic gneiss near Longwan, Qianxi County, 2518-2515 Ma, the Qiuhuayu trondjemitic gneiss at Zunhua 2515 Ma, the Xiaoguanzhuang tonalitic gneiss at Zunhua 2495 Ma, and the Cuizhangzi gneiss in Qianxi County 2492 Ma. These geochronilogical data demonstrate that, though diverse in composition, type and origin, the granitic gneisses in eastern Hebei Province were emplaced and crystallized in a rather short period of magmatic activity. The formation of such a great amount of gneisses in this small time gap suggests that it was a critical crust accretion stage at the end of Neoarchean. The fact that granitoids of various types occurred at the same time implies a large-scale underplating (mantle plume) activity, which was then responsible for the crust accretion. 展开更多
关键词 ORTHOGNEISS magmatic event NEOARCHEAN zircon age eastern hebei Province
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Important Events and Chronological Framework of the Early Precambrian Granulite Terrain,Northwestern Hebei Province 被引量:3
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作者 Geng Yuansheng, Liu Dunyi and Song BiaoInstitute of Geology, Chinese Academy of Geological Sciences, 26 Baiwanzhuang,Beijing 100037, China 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第4期466-479,共14页
Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been esta... Based on the chronological data and relevant geological evidence, the chronological framework of the major geological events of the granulite terrain in northwestern Hebei Province and its adjacent areas has been established. Basic lava eruption occurred in the span of 2868-2932 Ma, resulting in the formation of the early crust. The TTG magma emplacement took place c.2761 Ma ago. Subsequently basic magma intruded into the supracrustal rocks at 2650 Ma, resulting in crustal thickening. The thickening was enhanced at 2561-2503 Ma by the widespread intrusions of granodioritic magma. In the period of 2477-2461 Ma charnockite intruded, accompanied by regional granulite facies metamorphism. The second stage of granulite facies metamorphism occurred c. 2300 Ma ago, and finally pink granite intrusions at 2144-2087 Ma resulted in the formation of a granite zone. 展开更多
关键词 geological event Early Precambrian GEOCHRONOLOGY GRANULITE northwestern hebei
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Research on the Willingness to Accept Compensation and Compensation Sharing of Returning Land for Farming to Forestry in Zhangjiakou and Chengde Region 被引量:3
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作者 WANG Yan-xia1,CHEN Xu-dong1,ZHANG Su-juan1,BAI Jie2,ZHANG Yi-wen3 1.Institute of Geographical Science,Hebei Academy of Science,Shijiazhuang 050011,China 2.Computer Department,Hebei Vocational College of Politics and Law,Shijiazhuang 050081,China 3.College of Resources and Environment Science,Hebei Normal University,Hebei Key Laboratory of Environmental Change and Ecological Construction,Shijiazhuang 050016,China 《Meteorological and Environmental Research》 CAS 2011年第5期41-44,共4页
[Objective] The aim was to study the willingness to accept compensation and compensation sharing of returning land for farming to forestry in Zhangjiakou and Chengde region.[Method] Based on the investigation of farm... [Objective] The aim was to study the willingness to accept compensation and compensation sharing of returning land for farming to forestry in Zhangjiakou and Chengde region.[Method] Based on the investigation of farmers’ willingness to accept ecological compensation in Zhangjiakou and Chengde region,farmers’ willingness to accept compensation was quantized,and the calculation model of sharing rate of ecological compensation was established,finally the sharing rate of ecological compensation was calculated choosing water supply quantity as reference.[Result] Farmers’ willingness to accept compensation in Zhangjiakou and Chengde region was 2 740.5 yuan/(hm2·a),and returned farmland area was 429 700 hm2 in 2008,so the willingness to accept ecological compensation was up to 1.178 billion yuan/a.In addition,the ecological compensation sharing rate of government was 37.60% in Beijing,42.75% in Tianjing and 19.64% in Tangshan,and their ecological compensation funds were 443,504 and 231 million yuan,respectively.[Conclusion] The study could provide important foundation for the establishment of ecological compensation standard and implementation of ecological compensation in Zhangjiakou and Chengde region. 展开更多
关键词 Zhangjiakou chengde Ecological compensation Willingness to accept compensation Sharing rate of compensation China
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Observations of coastal aeolian dune movements at Feicuidao, on the Changli Gold Coast in Hebei Province 被引量:3
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作者 YuXiang Dong DeQuan Huang JianHui Du 《Research in Cold and Arid Regions》 CSCD 2013年第3期324-330,共7页
High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei... High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei Province in 2006-2008. Our data provide information on the direction, type, and velocity of coastal dune movements, and indicate that the coastal dunes in this re- gion are characterized as slow and landward advancing, with to-and-fro fluctuations. The bottom of the studied coastal transverse ridge was stable during the observation period but the position of its crest advanced eastward (seaward) during summer and au- tumn, and moved landward (westward) in winter and spring. Thus, its crest moved generally landward (westward) but fluctuated to-and-fro eastward and westward. In contrast, the entire coastal crescent dune advanced landward (westward) in a to-and-fro manner, and the velocity of its movement was faster than that of the transverse ridge dune. These results are mainly related to the wind conditions in the research area, the height and volume of the two types of coastal dunes. 展开更多
关键词 coastal dune MOVEMENT observation Changli in hebei Province
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Tree ring analysis for determination of pollution history of Chengde City,north China 被引量:1
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作者 Jiang Gaoming(Institute of Botany, Chinese Academy of Sciences,Beijing 100044,China ) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第1期77-85,共9页
Air pollution history of sulphur and heavy metals since 1800 in Chengde City , north China,was studied by analyzing the concentrations of sulphur and heavy metals in growth rings of Pinus tabulaeformis Carr. Sulphur c... Air pollution history of sulphur and heavy metals since 1800 in Chengde City , north China,was studied by analyzing the concentrations of sulphur and heavy metals in growth rings of Pinus tabulaeformis Carr. Sulphur concentrations in the tree rings of 1910-1920, 1970-1980,and 1980-1990 have increased 1-2 , 3-5 and 10 times respectively as those in the tree ring of 1810-1820 (P<0. 05). This is ascribed to the result of urbanization, especially the appearance and aggravation of industrialization, in the city of Chengde since 1950s. Fe appeared to increase during 1920-1940, possibly due to the opening of Damiao Iron Mine by the Japanese in 1927; Mn increased throughout the whole history, from 4. 1 μg/g(1840- 1850) to 10. 4 μg/g (1980 1990,P <0. 05);Pb did not increase until 1980 but increased sharply during the last 10 years by 560%(P<0. 001). This is caused by the increased number of automobiles in the city. The contents of Cu,Zn, Ni have changed little. The concentrations of sulphur and heavy metals in the tree rings at the beginning of 1800s were the lowest and could be regarded as the background concentrations.We calculated that S, Fe, Pb, Mn, Ni, and Zn in the tree rings have increased 10, 2.4,1.8,1.5,1.0 and 0. 8 times respectively during the past 190 years or so. The results showed that serious environmental pollution, especially air pollution of SO2,has occurred since 1949 when the People's Republic of China was founded. 展开更多
关键词 tree rings Pinus tabulaeformis sulphur and heavy metals pollution history chengde
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Diagnostic Analysis of a Snowfall Weather in Beijing,Tianjin and Hebei in 2010 被引量:2
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作者 ZHOU He-ling CHEN Min 《Meteorological and Environmental Research》 2012年第1期32-35,40,共5页
[ Objective] The research aimed to analyze a local snowstorm weather process which happened in Beijing, Tianjin and Hebei during I - 4 January, 2010. [ Method] Based on routine meteorological observation data and NCEP... [ Objective] The research aimed to analyze a local snowstorm weather process which happened in Beijing, Tianjin and Hebei during I - 4 January, 2010. [ Method] Based on routine meteorological observation data and NCEP/NCAR 2.5° ×2.5° grid data (four times every day), a lo- cal snowstorm weather process which happened in Beijing, Tianjin and Hebei during 1 -4 January, 2010 was carried out diagnostic analysis by using composite analysis method. [Result] Circumfluence on the ground and strong cold advection in the rear of upper trough were the main weath- er system of the snowfall. The deep thick wet layer and strong water vapor convergence provided sufficient water vapor for snowfall. The divergence field of low-level convergence and high^level divergence, dynamic coupling effect of vorticity provided favorable dynamic condition upwardly for the occurrence of strong snowfall. The steep dense area of Oso, low temperature at the ground layer and inversion temperature at the high layer provided certain energy condition for the development of snowfall weather. [ Conclusion] The research provided theoretical basis for snowfall forecast in future. 展开更多
关键词 SNOWFALL Physical quantity Diagnostic analysis Beijing Tianjin and hebei China
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Application of the Gravity Method to the Iron Ore Exploration in Eastern Hebei Province 被引量:5
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作者 ZHANG Guoli ZHAO Gengxin +3 位作者 HE Fuqing SU Yongjun TENG Fei KUANG Haiyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期2097-2098,共2页
The nation-wide iron ore exploration is primarily based on aeromagnetic survey,based upon which a series of ground follow-up and drilling examination were carried out,and then reconnaissance and detailed investigation... The nation-wide iron ore exploration is primarily based on aeromagnetic survey,based upon which a series of ground follow-up and drilling examination were carried out,and then reconnaissance and detailed investigation and exploration were fulfilled.However,for some large. 展开更多
关键词 Application of the Gravity Method to the Iron Ore Exploration in Eastern hebei Province
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Influence of “Holiday Tourism Circle of Beijing” on Chengde Tourism Spatial Alteration and Reconstruction
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作者 Li Chen1,2,Cheng Shengkui2,Chen Yuansheng2,Zhang Yingqiu1 1.College of Arts&Science,Beijing Union University,Beijing 100083,China 2.Institute of Geographical Science and Natural Resources Research,CAS,Beijing 100101,China 《Chinese Journal of Population,Resources and Environment》 北大核心 2006年第4期38-42,共5页
Chengde City,famous for its cultural sightseeing tourism industry,and is located in China's"Capital Holiday Tourism Circle".This location is advantageous,because of the recent boom in China's nationa... Chengde City,famous for its cultural sightseeing tourism industry,and is located in China's"Capital Holiday Tourism Circle".This location is advantageous,because of the recent boom in China's national tourism industry.This industry has gone through several structural and development changes with in the past several years.A result of these restructuring patterns is the great changes concerning competitive and cooperative relations among tourism destinations,which have precipitated the decline of the traditional sightseeing pattern. Northern China's"Capital Holiday Tourism Circle"is one of nine key areas within the Chinese tourism industry under development during the Eleventh Five-Year Plan.In the present article the method of"Distance Decline of The Tourist Flow"was used to define the flow of tourists in the Capital Holiday Tourism Circle and its influence upon Chengde's tourism spatial distribution.3 aspects will be discussed:(1)The transformation from sightseeing to leisure markets makes the change possible in Chengde's tourism spatial pattern.(2)The location advantage(adjacent to Beijing and Tianjin) also leads to the change in Chengde tourism spatial pattern.(3)The establishment of freeways also contributes to a great degrees of change. The rapid development of leisure tourism might lead to the change from nucleus model to a diversified one within Chengde's tourism.Specifically,Chengde is developing the tourism industry with the central heritage area as the nucleus and the northern forest, pasture,southern mountain,and rivers as its periphery. 展开更多
关键词 China CAPITAL HOLIDAY TOURISM Circle chengde city TOURISM space
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Tectonic Environments of the Yan-Liao Rift during Earth's Middle Age(1.7~0.75 Ga): Evidence from Mafic Dyke Swarms in Eastern Hebei, North China 被引量:1
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作者 WANG Chong PENG Peng +1 位作者 WANG Xinping YANG Shuyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期45-46,共2页
During the past decade,generations of Precambrian mafic dykes/sills have been investigated and revealed in the North China Craton(NCC).Researchers identified more than 20 episodes of Precambrian dyke swarms,
关键词 North China Tectonic Environments of the Yan-Liao Rift during Earth’s Middle Age Evidence from Mafic Dyke Swarms in Eastern hebei Ga
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Geochemistry and Genesis of the Sodium-Charnockitic Gneisses, Eastern Hebei Province, China
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作者 Wang Anjian Changchun University of Earth Sciences, Changchun, Jilin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1992年第3期239-258,共20页
High in sodium and low in potassium (Na_2O/ K_2O>1), the charnockitic gneiss series in theSantunying- Taipingzhai area, eastern Hebei province, consists of hypersthene- quartz- diorite,hypersthene-granodiorite and ... High in sodium and low in potassium (Na_2O/ K_2O>1), the charnockitic gneiss series in theSantunying- Taipingzhai area, eastern Hebei province, consists of hypersthene- quartz- diorite,hypersthene-granodiorite and hypersthene-plagioclase-granite. Geological, petrological and large ion lithophileelement(LILE), high field strength element (HFSE) and REE geochemical studies suggest that themedium-coarse-grained hypersthene-granodiorite is the product of crystallization of anatectic magmas of thesame composition. Under granulite facies conditions, the equilibrium crystallization differentiation of themagmas yielded the early crystallization phase-high-SiO_2, LILE-depleted, low-∑REE, positive Eu anomalyand REE- saturated hypersthene- plagioclase- granite. The residual phase, coarse- grained to pegmatitichypersthene- granodiorite, is marked by low SiO_2, LILE-enrichment, high ∑REE and REE-undersaturation.These rocks and hypersthene-quartz-diorite enclaves constitute the sodium-charnockitic gneiss series in easternHebei province. Model calculation for trace elements in the granitoids was applied. On the basis of a systematicgeological study, the equation for calculation was chosen, the source magma was determined and the partitioncoefficients were obtained. The resulting curves are entirely consistent with those observed in the patterns of ac-tual rocks. The study indicates that whole-rock REE patterns can not be used directly in the comparison of thesources and genesis of granitoids. 展开更多
关键词 sodium-charnockitic gneisses GEOCHEMISTRY GENESIS eastern hebei province
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Palaeohydrological reconstructions achieved from palaeoclimatic conditions and palaeochannel morphology for southern Hebei,the North China Plain
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作者 WANG Hong-ya XIE Qiang(Peking University, Beijing 100871, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第1期1-14,共14页
Palaeorunoff regimes were reconstructed using the equations relating annual runoff to climatic parameters and palaeoclimatic information acquired mainly by pollen analysis and peat investigation for southem Hebei (114... Palaeorunoff regimes were reconstructed using the equations relating annual runoff to climatic parameters and palaeoclimatic information acquired mainly by pollen analysis and peat investigation for southem Hebei (114~117°E, 36~38°N) during the last 70 000 years. With the morphological data of palaeochannels preserved in the same region, discharge estimates were calculated with the equations relating discharge to morphological parameters of channel for the palaeorivers acting during the last 25 000 years. For the last 25 000 years, the reconstructed palaeorunoff regimes were compared to the corresponding palaeodischarge ones. This comparison indicates the same trend of hydrological changes occurring in southern Hebei during the last 25 000 years. During 8 000~25 000 or 7 500~25 000 a B.P, the quantity of surface water was rather small and probably just 46 or 60 percent of the one for the interval of 3 000~8 000 or 2 500~7 500 a B.P The surface water was the least during 0~3 000 or 0~2 500 a B.P, being 34 or 33 percent of the one occurring during 3 000~8 000 or 2 500~7 500 a B.P The maximum surface water occurred during 3 000~8 000 or 2 500~7 500 a B.P. when the runoff ranged 147.6~398.0 mm and discharge 210-324 m3/s. 展开更多
关键词 PALAEOHYDROLOGY PALAEOCLIMATE PALAEOCHANNEL southern hebei
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Studies on Water Consumption Characteristics and Crops Rotation Effects in Plateau of Northern Hebei Province
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作者 ZHANG Li-feng, BIAN Xiu-ju and LIU Yu-hua(Hebei Agricultural University, Bonding 071001 ) 《Agricultural Sciences in China》 CAS CSCD 2002年第1期76-80,共5页
Experiments were carried out in 1994 - 1998 to study crop rotation and its effects on crop water consumption characteristics of field with sandy chestnut soil in the Plateau of north Hebei Province. Five crops includi... Experiments were carried out in 1994 - 1998 to study crop rotation and its effects on crop water consumption characteristics of field with sandy chestnut soil in the Plateau of north Hebei Province. Five crops including spring wheat, oat, pea, flax and potato were examined. There was little difference in field water consumption among the crops during the growing season. WUE varied significantly in a range of 1. 347 -11.177kg · ha-1 · mm-1 among crops and 11.44% - 46.66% among previous crops. It was pointed out that the land equivalent ratio (LER) can be used as an index to evaluate the biological effects of crop rotation comprehensively. The 2-4 year crop rotation patterns with higher LER were estimated in the paper. 展开更多
关键词 ROTATION Water consumption WUE LER Plateau of north hebei Province
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Magmatism, Deep Processes and Gold Deposits in Eastern Hebei, China
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作者 Zhao Hailing Deng Jinfu Li Kaiming Xu Liquan Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 1999年第1期71-75,共5页
The eastern Hebei Province of China is one of the major concentrating areas of gold mineralization in eastern China, which is an important part of the circum Pacific magmatic tectonic metallogenic belt. There are t... The eastern Hebei Province of China is one of the major concentrating areas of gold mineralization in eastern China, which is an important part of the circum Pacific magmatic tectonic metallogenic belt. There are three types of gold deposits in terms of the characteristics of host rocks. Jinchangyu type gold deposit is situated in the Archean metamorphic basement. Yuerya type gold deposit occurs within the Yanshanian granite. Lengkou (or Wanzhuang ) type gold deposit is located within the covering strata of the Mesoproterozoic dolomitite. These 3 types of gold deposits are very similar in many respects. These deposits formed at Mesozoic and their spatial distribution is closely related to Yanshanian granite. The mineralization characteristics of these gold deposits are very similar. The characteristics of sulfur isotopic and lead isotopic compositions show that the gold deposits in this area are derived from the mantle and deep crust, and are related to Mesozoic magmatism. The gold deposits in this area are believed to be the products of crust mantle exchange and resulted from multistage gold mineralization. Finally a mineralization model of gold deposit in eastern Hebei of China is proposed. 展开更多
关键词 deep processes gold deposit Yanshanian granite mineralization model eastern hebei of China.
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Dynamic Changes of Land Use in Built-up Area of Chengde City in the Past 14 Years
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作者 SUN Baisheng 《Journal of Landscape Research》 2016年第4期42-44,共3页
Landsat TM/OLI images of the built-up areas in Chengde City(Shuangqiao District and Shuangluan District) in 2000,2009 and 2014 were adopted,Support Vector Machine(SVM) was applied to classify the images automatically,... Landsat TM/OLI images of the built-up areas in Chengde City(Shuangqiao District and Shuangluan District) in 2000,2009 and 2014 were adopted,Support Vector Machine(SVM) was applied to classify the images automatically,land use/cover map of the study area was obtained after precision test.Through analyzing the land use types in the study area and also applying transfer matrix to monitor the changes,the results showed that human activities and urbanization in the past 14 years have brought the increasing tendency of construction land,and the negative growth of arable land,forest and shrubbery land.It is urgent to adopt corresponding measures to maintain the coverage of forest and shrubbery land in the built-up area of Chengde City,so as to reduce the impact of human activities and improve urban ecological environment. 展开更多
关键词 Land coverage Change monitoring chengde City
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Damage Symptoms and Damage Degree of Main Diseases and Pests in Foxtail Millet in Chengde Area
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作者 Fan Qingjie Zhang Yingying +2 位作者 Shi Aili Xing Zhanmin Kang Liang 《Plant Diseases and Pests》 CAS 2018年第1期12-16,共5页
The species of main diseases and pests in foxtail millet and their damage status were investigated in 15 survey points in Longhua, Weichang, Chengde, Fengning and Luanping counties, Chengde City from 2015 to 2017. It ... The species of main diseases and pests in foxtail millet and their damage status were investigated in 15 survey points in Longhua, Weichang, Chengde, Fengning and Luanping counties, Chengde City from 2015 to 2017. It was preliminarily cleared that there were 11 species of main diseases and 8 species of pests in continuous cropping millet field. The diseases damaged severely were millet downy mildew and kernel smut, and pests were yellow-legged lema, millet shoot fly and soil insects. The results provided a scientific basis for green control of millet pests and diseases and safe production in Chengde area. 展开更多
关键词 chengde area Foxtail millet Diseases and pests Damage symptoms Damage degree
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Element migration and enrichment characteristics of bedrock–regolith–soil–plant continuum system in the chestnut planting area,Chengde,China
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作者 Xiaofeng Wei Houyun Sun +4 位作者 Zirang Chen Xia Li Hao Wei Wenru Jia Wei Li 《Acta Geochimica》 EI CAS CSCD 2022年第5期839-860,共22页
In order to probe the geochemical relationship between the quality of economic crops and ecological geochemistry,this project studies the chestnut production area of Chengde City,Hebei Province,China.The chemical weat... In order to probe the geochemical relationship between the quality of economic crops and ecological geochemistry,this project studies the chestnut production area of Chengde City,Hebei Province,China.The chemical weathering index,chemical depletion fraction CDF,mass transfer coefficient,and bioconcentration coefficient were used to quantify the characteristics of element migration and accumulation in the BRSPC(Bedrock–Regolith–Soil–Plant Continuum system)system of gneiss formation area and dolomite formation area.The results show that the soil CaO,SiO_(2),Al_(2)O_(3),and Na_(2)O elements in the gneiss construction area are abundant,and the B,Ge,S,and Mo elements are relatively lacking;the soil B,Mo and Ge elements in the dolomite construction area are abundant,and the SiO_(2),Al_(2)O_(3),and Na_(2)O elements are slightly lower;The weathering intensity of gneiss is low-medium,with the relatively high mobility and apparent transformation of Se,B,V,S,Mn,and Mo.The weathering intensity of dolostone is low,with the relatively high mobility and apparent transformation of Na_(2)O,P,and Ni.Chestnut is rich in Cu,Ni,Se,and Ge,walnut has a high content of Mo,and hawthorn is rich in Se and B.The contents of Mn in chestnut are 1–2 times higher in walnut and hawthorn.It lays the theoretical foundation for the industry optimization of special industrial crop planting in Chengde according to our research. 展开更多
关键词 Critical zone Eco-geochemistry Element migration CHESTNUT chengde
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Study on Quinoa Characteristics in Central and Southern Hebei
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作者 Zhimin WEI Hanzhang ZHOU +5 位作者 Fei LIU Meng LIU Yu ZHAO Xueyan XIA Shunguo LI Wei LU 《Asian Agricultural Research》 2017年第12期82-84,共3页
Quinoa is rich in nutrients and has high economic value,which attracts people's attention.Given that the quinoa has not yet been planted in the low-altitude Central and Southern Hebei plain,we used the quinoa seed... Quinoa is rich in nutrients and has high economic value,which attracts people's attention.Given that the quinoa has not yet been planted in the low-altitude Central and Southern Hebei plain,we used the quinoa seeds from five different habitats in China to conduct a planting test under different date of seeding in the low-altitude Central and Southern Hebei plain,and obtained the comprehensive data about the phenophase and agronomic traits of quinoa in this region.The test results showed that the grain quinoa should not be planted in Central and Southern Hebei plain,the limiting factors were identified,and a new way for local development of vegetable quinoa was found. 展开更多
关键词 QUINOA Central and Southern hebei CULTIVATION
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